Mummy, that robot is making faces at me

时间：2017-06-15 02:00:13166网络整理admin

By Flora Graham Robotics engineers at the University of Bristol, UK, have been grimacing a lot recently, thanks to their copycat robotic head, Jules, which can mimic the facial expressions and lip movements of a human being. Jules is an animatronic head produced by US roboticist David Hanson, who builds uniquely expressive, disembodied heads with flexible rubber skin that is moved by 34 servo motors. Human face movements are picked up by a video camera and mapped onto the tiny electronic motors in Jules’ skin. The Bristol team developed its own software to transfer expressions recorded by the video camera into commands to make those servos produce similarly realistic facial movements. However, because the robot’s motors are not identical to human facial muscles, some artistic licence was required. After filming an actor making a variety of expressions indicating, say, “happiness”, an expert animator selected 10 frames showing different variations of the expression and manually set the servos in Jules’s face to match. That training was used to create software that can translate what it sees on video into equivalent settings of Jules’s facial motors. The robot can now do this in real time, at 25 frames per second. Copycat robot heads have been created before, but not with realistic human-looking faces. For example, the Kismet robot developed at MIT in the United States has complex facial expressions, but a mechanical metal face that looks like a Muppet version of the Terminator robot. Jules’ human appearance makes getting the expressions perfect even more critical, to avoid the notorious “uncanny valley“. This describes the way that human-like robots or animations that are not quite true-to-life are perceived as unnerving, while less realistic versions, perhaps looking very mechanical, are less alarming. “We are really attuned to how a face moves, and if it’s slightly wrong, it gives us a feeling that the head is somehow creepy,” explains Neill Campbell, who led the research. “Research has shown that if you have a robot that has many human-like features, then people might actually react negatively towards it,” agrees Kerstin Dautenhahn, a robotics researcher at the University of Hertfordshire in the UK, who calls Jules’ copycat routine “very impressive”. But reaching the other side of the uncanny valley – achieving such realism that people react to robots as they do to humans – would have significant benefits, says Campbell. Human communication relies heavily on facial expressions, so robots that can mimic them well should find much wider application. He anticipates that this would make them useful in healthcare settings, such as nursing homes. However Dautenhahn questions the ethical implications of using very human-like robots for more than entertainment. “If you expose vulnerable people, like children or elderly people, to something that they might mistake for human, then you would automatically encourage a social relationship,” she told New Scientist. “They might easily be fooled to think that this robot not only looks like a human and behaves like a human, but that it can also feel like a human… and that’s not true.” Journal reference: Robotics and Autonomous Systems (DOI: 10.1016/j.robot.2008.09.002) Robots – Learn more about the robotics revolution in our continually updated special report. More on these topics: